"There will always be people who we know .. . but we've appointed lots of people that have political linkages to our opponents.
"We did send Mike Moore as the ambassador to Washington, our single biggest post overseas, the former leader of the Labour Party. If you look at the vast array of appointments we make, I think the balance is about right."
National also appointed former Labour deputy leader Michael Cullen to the deputy chair and then the chair of NZ Post.
Screen Production and Development Association chief executive Penelope Borland, in her latest newsletter to members, called for bipartisan board appointments.
"While all appointments to the board of NZ On Air are 'political' as in appointed by ministers, the appointment of active party political figures may be a step too far as board members need to maintain neutrality and put aside their political interests.
"Ideally, appointments should be made on a bipartisan basis."
She said NZ on Air should never have taken the matter up with TV3.
"Once NZ On Air satisfies itself that the programme meets its investment criteria that's where its role stops. Scheduling, editorial or content is the role of the broadcaster and NZ On Air should not get involved."
Mr Key was on the defensive again when it was revealed former Act Party president Catherine Isaac was in line to lead a group overseeing the implementation of the charter school trials in South Auckland and Christchurch.
Mr Key said he would be comfortable if Ms Isaac took on the role, which was yet to be finalised.
Appointments under National
Judy Kirk, former National president, chair the board of the NZ Lotteries Commission
Don Brash, former National leader, chair of the 2025 taskforce
John Carter, former National Minister, High Commissioner to the Cook Islands
Mark Blumsky, former National MP, High Commissioner to Niue
Brian Neeson, former National MP, a member of the Human Rights Review Tribunal
Roger Sowry, former National MP and Minister, board member of the Electricity Authority and chair of two polytechnic councils
Belinda Vernon, former National MP, board member of the Institute of Geological and Nuclear Sciences.
Jenny Shipley, former National Prime Minister, appointed to chair Genesis and now monitors the Canterbury Earthquake Recovery Authority
Kerry Prendergast, former National candidate, head of the Tourism Board
Stephen McElrea, John Key's electorate chair and National deputy chair of the northern region, board member of NZ On Air
Appointments under Labour
Jonathan Hunt, former Labour Minister, appointed High Commissioner in London
Mike Williams, former Labour president, deputy chair Genesis Power, director of Ontrack, GNS Science, board membership of the New Zealand Transport Agency
Jim Sutton, former Labour minister, deputy chair of the New Zealand Lotteries Commission and Meridian Energy
Graeme Kelly, former Labour MP, appointed High Commissioner to Canada
Stan Rodger, former Labour minister, appointed commissioner of the Electricity Commission, director of NZ Post and chair of the Health Workforce Advisory Group.
Dianne Yates, former Labour MP, appointed to the board of the Food Safety Authority
Jenny Kirk, former Labour MP, appointed to the board of the Cadastral Surveyors Licensing Board